WET News

Set concrete proves a drainage problem • Cleaning construction site equipment after use may be necessary where concrete is involved, but the wash-down water can block drainage systems. fouling removal aer other more traditional jetting and cleaning has failed to remove the blockage. Clients are usu- ally at the point where the fouling problem is seemingly impossible to overcome, and consider pipe replacement as the only option. Aer decades of operation in the field Tube Tech has developed a range of simple yet effective remote control systems and robotics specifi- cally for fouling removal pur- poses. In many cases equip- ment suited to the scheme in hand may be developed. The requirement to re-es- tablish the correct flow regime in the concrete laden pipes serving the new buildings proved to be urgent. Tube Tech was asked initially to rapidly mobilise with what might be the best equipment available to it at the time. The company has continu- ally developed tried and tested, step change methods to solve heavy industries' most difficult fouling removal chal- lenges worldwide providing simultaneous re-opening and inspection services for a wide variety of industrial situations enabling significant savings to be made by clients by reducing downtime, cutting CO2 emis- sions, increasing throughput and improving safety standards. Previous experience in the removal of concrete from pipework enabled Tube Tech to bring to the site one of its proven systems. This option had some effect for removing the concrete in the pipes at up to four times more than any previous contractor. However, this still proved too time-con- suming an option for the client. What made the works some- what more demanding was ONSITE TRENCHLESS TECHNOLOGY Access to and from the cleaning locations was difficult in amongst the ongoing construction works A cleaning access location within the building structure Cleaning equipment in one of the manholes that there were no drawings of the pipe network available so until the Tube Tech team arrived on site any cleaning work was effectively done blind. Aer the initial attempts to remove the concrete proved too slow, Tube Tech's expertise was brought to bear given the experience and better under- standing of the problem. The L ondon, like many of the world's largest cities and towns, is seeing major building works including some of the largest new-build, pur- pose-built accommodation developments to date. During the construction operations, machinery and equipment are oen washed down aer use to ensure they are in the best work- ing order. Where such equipment has been used for the preparation, movement or installation of concrete this can cause prob- lems for the drainage system as wash-down water makes its way off site into the local drainage network. Done over time, this can cause even newly laid drainage pipes to become laden with set con- crete that has to be removed to ensure the long-term viability of the drainage system. This was the case recently on a major construction under- taking for a residential con- struction project in the Dock- lands area in London's East End. Having sought the market for potential options to clean the affected pipes, and trial- ling cleaning from various cleaning contractors, the deal to complete the concrete removal process was awarded to specialist pipe cleaning company Tube Tech Interna- tional, of Rayleigh, Essex. Tube Tech is oen called on to implement its specialist 14 WET NEWS JANUARY 2018 team regrouped and developed better technology to cope with the limited access to the affected pipeline within the confines of the construction site; handle the tight bends; and be a faster concrete clear- ing method. Part of this solution was the development and introduction of the use of polymer infused ultra-high pressure water, to create more impact against concrete blockages and remove it quicker. Tube Tech found a biodegradable chemical that could be used to soen the set concrete in advance of any cleaning operation. This, alongside the use of various mechanical tooling and high pressure jetting, meant the use of four different technologies was required to achieve full removal of the concrete obstruction in the drainage pipe. The success of the fouling removal operation was eventu- ally complete in just five work- ing days. One of the more important aspects of the site work, as well as completing clearing of the concrete obstruction, was limiting any potential damage to the pipeline material. As with any situation where the obstructing material is harder than that from which the pipe is made, there is always the potential for dam- age to be incurred by the pipe fabric. This was the case on the

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